Clinical and radiological outcomes of conservative treatment for unilateral sagittal split fractures of C1 lateral mass

Abstract

ObjectiveThe aim of this study was to assess the effect of transverse atlantal ligament (TAL) integrity on clinical and radiological outcomes in patients with unilateral sagittal split fracture (USSF) of the C1 lateral mass (LM).MethodsTwenty-six consecutive patients (16 men and 10 women; mean age: 52 years (range: 32–69)) with C1 LM USSF were included in this study. Sixteen were TAL injury group (nine of type I injuries and seven of type II injuries according to Dickman's classification) and ten were TAL intact group. All cases were conservatively treated with a rigid brace for TAL intact or by halo-vest stabilization for TAL injury for three months. The mean follow-up was 16 months (range, 12–47 months). The results were compared with radiological assessment of fracture healing, LM displacement and Neck visual analog scale.ResultsAt the last follow-up, for TAL intact group, total LM displacement (LMD), unilateral LMD of fracture side, atlanto-dental interval, basion-dental interval, clivus canal angle, and atlanto-occipital joint axis angle were maintained compared to initial presentation. However, for TAL injury group, all radiological parameters were worsened. The worsening of radiological parameters was more severe in type I injury than type II injury except for total LMD and unilateral LMD. Neck visual analog scale significantly decreased and patient's satisfaction was higher in TAL intact group compared to TAL injury group.ConclusionConservative treatment for USSF of C1 LM with TAL injury failed to achieve healing of the fracture, which resulted in lateral displacement of C1 LM. This caused coronal and sagittal malalignment of occipitocervical junction, resulting in unsatisfactory clinical outcomes. Our results suggest that early surgical stabilization should be considered in USSF of C1 LM with TAL injury, especially type I injury. However, conservative treatment may be sufficient for a USSF of the C1 LM with TAL intact.Level of EvidenceLevel III, Therapeutic Study.

Diagnosis and management of isolated C1 fractures: A systematic review

“…A total of 305 articles were returned in the database searches, of which 13 articles were included in this systematic review. [ 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 ] [ Figure 1 ] demonstrates the PRISMA flow diagram for this study. Study design included 10 (73.3%) case series and 2 (20.0%) retrospective cohort studies and 1 (6.7%) prospective cohort study.…”

“…Ten articles reviewed treatment of patients presenting with isolated atlas fractures [ Table 2 ]. [ 12 , 13 , 14 , 15 , 16 , 17 , 18 , 21 , 22 , 24 ] Three studies utilized the Rule of Spence in the classification of TAL injury and subsequent management. [ 16 , 18 , 21 ] All six studies examining outcomes of unstable atlas fractures found favorable fusion rates with any form of surgery,[ 12 , 13 , 14 , 18 , 22 , 24 ] while one study examining stable atlas fractures found favorable fusion rates with conservative management.…”

“…[ 12 , 13 , 14 , 22 ] Five studies examined VAS pain scores. [ 12 , 17 , 18 , 22 , 24 ] Two studies reported improvement in VAS pain score in all patients after surgery. [ 12 , 22 ] Another study determined that the mean VAS pain score improved from 6.92 + 0.76 preoperatively to 2.08 ± 0.64 postoperatively in surgically managed patients and from 7.18 ± 0.75 to 2.91 ± 1.70 in patients managed with halo vest, with no difference between the groups.…”

“…[ 18 ] One study determined that neck VAS pain score significantly decreased in patients with unilateral sagittal split fracture managed conservatively with the TAL intact but not those with TAL injury. [ 17 ] Shatsky et al . reported a VAS score of 0.7 at last follow-up.…”

“…Four studies measured various radiographic values including LMD. [ 14 , 17 , 18 , 24 ] Kim and Shin determined that LMD significantly decreased after posterior C1 lateral mass screw–C2 pedicle screw fixation relative to halo vest immobilization. [ 18 ] Two studies utilizing surgical approaches of transoral osteosynthesis and posterior osteosynthesis determined that LMD decreased after surgery.…”